Agricultural combines gather crop plants from the ground, separate the actual crop from the residue, and then distribute the residue over the ground behind the combine. It is desirable to spread residue evenly over the ground behind the combine, covering the ground that has just been harvested.
Agricultural harvesting heads are supported on the front of the agricultural combines to sever the crop from the ground and feed the severed crop plants into the combine itself. The harvesting heads are typically supported on a conveyor housing (a.k.a. “feeder house” or “inclined elevator”) that extends forward from the agricultural combine.
Agricultural harvesting heads such as draper platforms use left and right side conveyor belts to bring the crop inwardly from each side of the head to a central location. The cut crop material is then deposited on a center conveyor belt which feeds the cut crop material rearward, and underneath a feed drum (a type conveyor) supported at the rear of the agricultural harvesting head. The feed drum rotates, and engages the thick mat of cut crop material with fingers that extend from the feed drum.
As the feed drum is driven in rotation, it draws the fingers to the rear of the agricultural harvesting head. The fingers engage the crop mat as they are drawn to the rear and drag the crop mat underneath the feed drum. The fingers withdraw into the feed drum as the drum rotates to the rear, thereby releasing the crop mat and pushing the crop mat into the feeder house. A conveyor in the feeder house then draws the cut crop material upward, to the feeder house and deposits the cut crop material into the combine itself for further processing.
Newer agricultural harvesting heads have a larger crop capacity. As a result, the feed drums must be made with increased conveying capacity. One way to increase the capacity is to increase the dimensions of the feed drum. Another way is to increase the number of fingers extending from the drum to get a better grasp on the mat of cut crop material.
In perhaps the most common arrangement, an offset circular shaft is supported within the drum to which a finger mount is mounted. The finger mount is free to rotate about the circular shaft. A finger is connected to the finger mount at its inner end, and its outer end extends through a hole in the drum. The finger is typically connected to the drum with a quick release device such as a spring clip or pin. The drum is provided with a small removable cover fixed to its outer surface to cover and access hole. To repair a broken or missing finger and/or finger mount, the operator can open this cover, reach inside the drum, and replace the finger/finger mount by unclipping the finger from the finger mount, or and/or releasing the finger mount from the drum. The broken parts can be withdrawn through the access hole, the cover reattached, and the farmer can proceed with harvesting.
Providing each finger with its own individual finger mount limits the number fingers that can be mounted in the feed drum, however, since each individual finger requires its own individual portion of the shaft on which to mount.
It would be beneficial to attach more than one finger to a single finger mount. Indeed, several such arrangements have been investigated in the past.
U.S. Pat. No. 2,748,921 A and U.S. Pat. No. 2,557,226 A show a dual finger mount in the form of a member having an elongate straight slot, to which two diametrically opposed fingers are fixed. The offset circular shaft extends through the elongate slot, and as the drum rotates, translates the shaft up and down in the slot as it simultaneously reciprocates the two fingers fixed to the member back and forth through holes in the wall of the drum. This arrangement produces significant wear as the shaft slides up and down in the elongate slot. Further, the elongate slot is open and collects contaminants which may plug the ends of the slot. Since they are a part of a single rigid member, each pair of diametrically opposed fingers are fixed with respect to each other and do not move relative to each other.
U.S. Pat. No. 9,392,747 shows a dual finger mount similar to U.S. Pat. No. 2,748,921 and U.S. Pat. No. 2,557,226, above. In this arrangement, however, the slot is not straight (see U.S. Pat. No. 2,748,921), but is curved.
DE1507169 A1 shows a multiple finger mount in which rigid bars (1) extend completely through a drum (2) in both directions (each party thus forming 2 fingers that are 180° opposed). Three of these rigid bars (1) are fixed in parallel relation and laterally spaced apart to a longitudinally extending bar (3). The longitudinally extending bar (3) is supported at each end on cam tracks (6). The cam tracks (6) are stationary, whereas the rigid bars and the longitudinally extending bar to which they are fixed is a solid assembly that translates inside the drum and rotates together with the drum. There is no offset shaft fixed within the drum about which the fingers rotate. Further, the two opposing fingers (formed by the two opposing ends of each rigid bar) are fixed with respect to each other, and do not move relative to each other.
U.S. Pat. No. 6,986,241 B2 shows an offset bar in which a row of parallel fingers (16) are attached to an elongate bar (36) that extends parallel to the longitudinal axis of the drum. Bearings (42) are fixed to the elongate bar (36) and are supported on a stationary shaft (32) to rotate about the shaft, thus permitting all of the parallel fingers (16) to rotate together with the drum and simultaneously extend and retract.
In the examples above, the finger mounts supporting multiple fingers are inflexible (i.e. they do not permit the multiple fingers to pivot with respect to each other), and they are long and unwieldy, and difficult to service and replace,
It is an object of this invention to provide a feed drum with fingers and finger mounts that avoids or reduces these limitations.